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排序方式: 共有109条查询结果,搜索用时 15 毫秒
1.
Ovarian cancer (OvCa) causes the highest mortality among all gynaecologic cancers. A large number of mRNA‐ or miRNA‐based signatures were identified for OvCa patient prognosis. However, the comprehensive analysis of function‐level prognostic signatures is currently not considered in OvCa. In the present study, we respectively inferred subpathway activities from mRNA and miRNA levels based on high‐throughput expression profiles and reconstructed subpathways. Firstly, the activities of two tumour pathways were calculated and the difference between normal and tumour samples were analysed using multiple tumour types. Then, we calculated subpathway activities for OvCa based on the expression profiles from both mRNA and miRNA levels. Furthermore, based on these subpathway activity matrices, we performed bootstrap analysis to obtain sub‐training sets and utilized univariate method to identify robust OvCa prognostic subpathways. A comprehensive comparison of subpathway results between these two levels was performed. As a result, we observed subpathway mutual exclusion trend between the levels of mRNA and miRNA, which indicated the necessary of combining mRNA‐miRNA levels. Finally, by using ICGC data as testing sets, we utilized two strategies to verify survival predictive power of the mRNA‐miRNA combined subpathway signatures and performed comparisons with results from individual levels. It was confirmed that our framework displayed application to identify robust and efficient prognostic signatures for OvCa, and the combined signatures indeed exhibited advantages over individual ones. In the study, we took a step forward in relevant novel integrated functional signatures for OvCa prognosis.  相似文献   
2.
Grain number is an important agronomic trait. We investigated the roles of chromatin interacting factor Oryza sativa VIN3‐LIKE 2 (OsVIL2), which controls plant biomass and yield in rice. Mutations in OsVIL2 led to shorter plants and fewer grains whereas its overexpression (OX) enhanced biomass production and grain numbers when compared with the wild type. RNA‐sequencing analyses revealed that 1958 genes were up‐regulated and 2096 genes were down‐regulated in the region of active division within the first internodes of OX plants. Chromatin immunoprecipitation analysis showed that, among the downregulated genes, OsVIL2 was directly associated with chromatins in the promoter region of CYTOKININ OXIDASE/DEHYDROGENASE2 (OsCKX2), a gene responsible for cytokinin degradation. Likewise, active cytokinin levels were increased in the OX plants. We conclude that OsVIL2 improves the production of biomass and grain by suppressing OsCKX2 chromatin.  相似文献   
3.
Chen  Yanting  Chen  Wen  Du  Cong  Fan  Lili  Wang  Wei  Gao  Min  Zhang  Yixin  Cui  Tingkai  Hao  Yunmeng  Pearce  Elizabeth N.  Wang  Chongdan  Zhang  Wanqi 《Biological trace element research》2019,188(1):52-59

Determination of the public health concern about magnesium (Mg) in health and disease has been confounded by the lack of a practical measure of status. This has resulted in a lack of consistency in associating Mg deficiency with specific pathological conditions. Some attempts at associating Mg with a chronic disease have used the Dietary Reference Intakes (DRIs) as a status assessment measure. Use of current DRIs for Mg is problematic because recent evidence suggests that they should be updated and based on body weight. An evidence-based suggested Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) for a 70-kg individual is 175 and 250 mg/day, respectively. However, numerous dietary and physiological factors can affect the need for Mg and thus affect the use of the current or suggested new DRIs to assess Mg status. Calcium intakes above normal requirements can decrease Mg balance and exacerbate signs of Mg deficiency. Mg deficiency apparently occurs often in obesity because of increased need to counteract the inflammatory stress induced by adipose tissue dysfunction. Deficiency in anti-oxidant nutrients such as vitamin E and selenium can exacerbate a response to low dietary Mg indicated by increased oxidative stress which can lead to chronic disease. Dietary modifiers of Mg absorption and excretion affect balance and thus the need for Mg. Factors decreasing Mg balance include low dietary protein and non-fermentable fiber, while factors that can increase balance include fructose and fermentable fiber and fructose-containing oligosaccharides. Use of the DRIs to assess the Mg status of a population or group needs to consider their physiological characteristics and dietary habits and be aware that the DRIs may need updating. The DRIs only can be considered a component of a toolbox that presently includes serum Mg concentration and the daily urinary Mg excretion to assess the Mg status of an individual.

  相似文献   
4.

Introduction

A growing body of literature reveals the causal pathways between physical activity and brain function, indicating that increasing physical activity among children could improve rather than undermine their scholastic performance. However, past studies of physical activity and scholastic performance among students often relied on parent-reported grade information, and did not explore whether the association varied among different levels of scholastic performance. Our study among fifth-grade students in Shanghai sought to determine the association between regular physical activity and teacher-reported academic performance scores (APS), with special attention to the differential associational patterns across different strata of scholastic performance.

Method

A total of 2,225 students were chosen through a stratified random sampling, and a complete sample of 1470 observations were used for analysis. We used a quantile regression analysis to explore whether the association between physical activity and teacher-reported APS differs by distribution of APS.

Results

Minimal-intensity physical activity such as walking was positively associated with academic performance scores (β = 0.13, SE = 0.04). The magnitude of the association tends to be larger at the lower end of the APS distribution (β = 0.24, SE = 0.08) than in the higher end of the distribution (β = 0.00, SE = 0.07).

Conclusion

Based upon teacher-reported student academic performance, there is no evidence that spending time on frequent physical activity would undermine student’s APS. Those students who are below the average in their academic performance could be worse off in academic performance if they give up minimal-intensity physical activity. Therefore, cutting physical activity time in schools could hurt the scholastic performance among those students who were already at higher risk for dropping out due to inadequate APS.  相似文献   
5.
To understand the molecular mechanism of male reproductive development in the model crop rice,we isolated a complete male sterile mutant post-meiotic deficient anther1 (pda1) from a γ-ray-treated rice mutant library.Genetic analysis revealed that the pda1 mutant was controlled by a recessive nucleus gene.The pda1 mutant anther seemed smaller with white appearance.Histological analysis demonstrated that the pda1 mutant anther undergoes normal early tapetum development without obvious altered meiosis.However,the pda1 mutant displayed obvious defects in postmeiotic tapetal development,abnormal degeneration occurred in the tapetal cells at stage 9 of anther development.Also we observed abnormal lipidic Ubisch bodies from the tapetal layer of the pda1 mutant,causing no obvious pollen exine formation.RT-PCR analysis indicated that the expression of genes involved in anther development including GAMYB,OsC4 and Wax-deficient anther1 (WDA1) was greatly reduced in the pda1 mutant anther.Using map-based cloning approach,the PDA1 gene was finely mapped between two markers HLF610 and HLF627 on chromosome 6 using 3,883 individuals of F2 population.The physical distance between HLF610 and HLF627 was about 194 kb.This work suggests that PDA1 is required for post-meiotic tapetal development and pollen/microspore formation in rice.  相似文献   
6.
7.
Zheng  Bao  Gao  Zhiyan  Liang  Liumei  Lu  Yunyu  Kong  Yongting  Chen  Wanting  Lin  Keying  Chen  Wanqi  Mai  Jingying  Li  Yanwen  Ma  Changling 《Molecular biology reports》2022,49(3):1895-1902
Molecular Biology Reports - Clonorchis sinensis was a food-borne zoonotic parasite in the worldwide and also an important risk factor of hepatic fibrosis. Excretory/secretion products of C....  相似文献   
8.
Transport of photoassimilates from leaf tissues (source regions) to the sink organs is essential for plant development. Here, we show that a phytohormone, the brassinosteroids (BRs) promotes pollen and seed development in rice by directly promoting expression of Carbon Starved Anther (CSA) which encodes a MYB domain protein. Over‐expression of the BR‐synthesis gene D11 or a BR‐signaling factor OsBZR1 results in higher sugar accumulation in developing anthers and seeds, as well as higher grain yield compared with control non‐transgenic plants. Conversely, knockdown of D11 or OsBZR1 expression causes defective pollen maturation and reduced seed size and weight, with less accumulation of starch in comparison with the control. Mechanically, OsBZR1 directly promotes CSA expression and CSA directly triggers expression of sugar partitioning and metabolic genes during pollen and seed development. These findings provide insight into how BRs enhance plant reproduction and grain yield in an important agricultural crop.  相似文献   
9.
Zhang Z  Zhang Y  Tan H  Wang Y  Li G  Liang W  Yuan Z  Hu J  Ren H  Zhang D 《The Plant cell》2011,23(2):681-700
Multicellular organisms contain a large number of formins; however, their physiological roles in plants remain poorly understood. Here, we reveal that formin homology 5 (FH5), a type II formin mutated in rice morphology determinant (rmd), plays a crucial role in determining rice (Oryza sativa) morphology. FH5/RMD encodes a formin-like protein consisting of an N-terminal phosphatase tensin (PTEN)-like domain, an FH1 domain, and an FH2 domain. The rmd mutants display a bending growth pattern in seedlings, are stunted as adult plants, and have aberrant inflorescence (panicle) and seed shape. Cytological analysis showed that rmd mutants have severe cell elongation defects and abnormal microtubule and microfilament arrays. FH5/RMD is ubiquitously expressed in rice tissues, and its protein localization to the chloroplast surface is mediated by the PTEN domain. Biochemical assays demonstrated that recombinant FH5 protein can nucleate actin polymerization from monomeric G-actin or actin/profilin complexes, cap the barbed end of actin filaments, and bundle actin filaments in vitro. Moreover, FH5 can directly bind to and bundle microtubules through its FH2 domain in vitro. Our findings suggest that the rice formin protein FH5 plays a critical role in determining plant morphology by regulating actin dynamics and proper spatial organization of microtubules and microfilaments.  相似文献   
10.
Huang W  Pi L  Liang W  Xu B  Wang H  Cai R  Huang H 《The Plant cell》2006,18(10):2479-2492
Polarity formation is central to leaf morphogenesis, and several key genes that function in adaxial-abaxial polarity establishment have been identified and characterized extensively. We previously reported that Arabidopsis thaliana ASYMMERTIC LEAVES1 (AS1) and AS2 are important in promoting leaf adaxial fates. We obtained an as2 enhancer mutant, asymmetric leaves enhancer3 (ae3), which demonstrated pleiotropic plant phenotypes, including a defective adaxial identity in some leaves. The ae3 as2 double mutant displayed severely abaxialized leaves, which were accompanied by elevated levels of leaf abaxial promoting genes FILAMENTOUS FLOWER, YABBY3, KANADI1 (KAN1), and KAN2 and a reduced level of the adaxial promoting gene REVOLUTA. We identified AE3, which encodes a putative 26S proteasome subunit RPN8a. Furthermore, double mutant combinations of as2 with other 26S subunit mutations, including rpt2a, rpt4a, rpt5a, rpn1a, rpn9a, pad1, and pbe1, all displayed comparable phenotypes with those of ae3 as2, albeit with varying phenotypic severity. Since these mutated genes encode subunits that are located in different parts of the 26S proteasome, it is possible that the proteolytic function of the 26S holoenzyme is involved in leaf polarity formation. Together, our findings reveal that posttranslational regulation is essential in proper leaf patterning.  相似文献   
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